Conventional active orthodontic appliances apply forces to the teeth of a patient. The forces gradually move the teeth into an arrangement that is more cosmetically appealing and/or functional. That is, the arrangement provides the patient with an improved appearance, and/or improved ability to chew, speak, and/or perform other functions.
Unfortunately, for a period of time after a patient ceases wearing an active orthodontic appliance, the teeth usually will shift from the desired arrangement. Therefore, generally patients wear a passive orthodontic retainer, for a period of time after the teeth have been moved into the desired arrangement by one or more active appliances. Patients wear the retainers to prevent their teeth from shifting until the teeth have stabilized in the desired arrangement.
However, conventional retainers have several problems. First, retainers are visible to others while the patient is wearing the retainer. Thus, patients consider retainers to be cosmetically undesirable. This is particularly true for retainers which must be worn 24 hours a day to prevent tooth movement. One attempted solution to this problem has been to make retainers removable. The patient removes such a retainer during the waking hours, and inserts the retainer only for sleeping. Notwithstanding, frequently the patient's teeth will shift in just a few hours, making insertion of the retainer for sleeping difficult.
Second, a retainer can cause difficulty in chewing. While retainers are generally less intrusive than an active orthodontic appliance, nonetheless such retainers often impair the patient's ability to chew and/or speak. This is especially true of retainers that include wires or ligatures that extend over the occlusal surfaces of the patient's teeth, and/or other structures that extend into the palette area of the patient's mouth.
Third, retainers generally only provide retention forces, which makes them passive orthodontic appliances. Thus, retainers cannot shift the teeth to a more desired arrangement. Notwithstanding, occasionally a situation requires the repositioning of one or two malposed teeth, which can only be accomplished by a more intrusive active appliance. To minimize the impact on the patient, a retainer is desired, rather than a conventional active appliance, that can reposition the malposed teeth, while maintaining the position of the other teeth.
The present invention provides an improved solution to these problems.